A novel bionic flower-like Z-scheme Bi4O5I2/g-C3N5 heterojunction with [formula omitted] active sites and π-conjugated structure for increasing photocatalytic oxidation of elemental mercury

Abstract

The carrier life regulation and redox media are key factors in photocatalytic purification of the environment. Herein, based on the specific π-conjugation network structure of g-C3N5, a novel Bi4O5I2/g-C3N5 Z-scheme heterojunction enriching I−/I3− active sites photocatalyst was creatively prepared, which properties were confirmed by X-ray photoelectron spectroscopy and photoelectrochemical analysis. Benefiting from the π conjugate network structure and I−/I3−redox medium, the photocatalytic activity of the as-prepared Bi4O5I2/g-C3N5 photocatalyst has been significantly improved by more than 3.1 times, and the highest photocatalytic mercury removal arrives up to 92.6%. This research proposes new enlightenment for the accelerated transport of electrons in heterojunction photocatalyst, which in turn contributes a highly efficient photocatalyst to control heavy metal pollutants in the flue gas at coal combustion power stations.